Brake mechanism.



H. G. BUHOUP.

BRAKE MECHANISM -APPLIUATION FILED MAR. 11, 1913.

1 91 428, Patented Dec. 16,1913. 9 3 SHEETS-SHEET 1.

IIIIIII I IIIIIIIIIIIIIIIII/Ir COLUMBIA PLANOURAPH co., WASHINGTDN, D c.

BRAKE MECHANISM.

APPLICATION-FILED MAR. 17, 1913.

Patented Dec. 16, 1913.

s sums-4111321 2.

:OLIJMBIA PLANOGRAPH 60-, WASHINDTON. D. C.

H. G. BUHOUP.

BRAKE MECHANISM.

APPLICATION FILED MAR.17, 1913.

1,081,428. Patented Dec. 16, 1913.

s SHEETS-SHEET a.

COLUMBM PLANOGRAPH C0-,WASHIN6TON. D. c.

HARRY C. BUI-IOUP, 0F CHICAGO, ILLINOIS.

BRAKE MECHANISM.

Specification of Letters Patent.

Patented Dec 16,1913.

Application filed March 17, 1918. Serial No. 754,782.

T 0 all whom it may concern Be it known that I, HARRY C. BUI-IO P, acitizen of the United States, residing at Chicago, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Brake Mechanisms; and I dohereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

My invention relates to the construction of brake mechanism for cartrucks, and especially to that class of brake mechanism wherein theweight of the car determines and controls the braking power exerted onthe wheels of the car truck.

The commonly adopted construction of' brake mechanism for car trucks isone in which the power is applied directly to the brake-shoes throughthe intermediation of the brake beams which carry the brake heads, andlevers with which the pull rod of the air brake mechanism is connected.As a result of this direct and uncontrolled application of the power tothe brake shoes, the same, or equal, power is applied to the brake shoeson the trucks of both heavy and light or loaded and empty cars, and thusthe braking power, which is approximately twenty thousand pounds pershoe for braking the wheels under a loaded or heavy car, is excessivefor braking the wheels under a lightly loaded or empty car, whichrequires only approximately six thousand pounds per shoe. Consequentlythe wheels under the lighter car will slide on the rails when subjectedto braking power sufficient for control of the heavier car. The slidingof the car wheels results in the production of fiat spots on the treadof the wheel limiting the mileage or life of the wheel, requiring themore or less frequent removal and replacement of wheels, and greatlyadding to the cost of maintenance of the rolling stock of a road.Further than this, where the wheels are caused to slide there is a greatloss of braking power. Also the commonly adopted construction of brakemechanism results in the locating of the brake-shoes between the wheels,and frequently below the centers thereof, so that the braking power whenapplied tends to raise the wheels, thereby reducing the friction betweenthe wheels and rails, which results in a proportionate loss of brakingpower.

A further disadvantage of the present construction of brake mechanismfor car trucks, resides in the inability to readily and convenientlyadjust, or remove and replace, worn brake shoes to compensate not onlyfor wear of the shoes, but also for unequal wear of the shoes. l/Vherethere is lost motion from brake shoe wear the excessive travel of theair-brake piston results in loss of braking power, and where the shoesare unequally worn, the application of the braking power tends to causetwisting or torsional strain on the brake-beams which carry thebrake-shoes.

The object of my present invention, therefore, is the production of asimple and etlicient brake mechanism, and one readily applicable to thepresent car truck construction, whereby the brake shoes, regardless ofunequal wear, shall exert uniform brak ing force upon the wheels, andwhereby the braking force shall be determined and controlled by theweight of the car, and the sliding of the wheels and the flatteningthereof be prevented; and whereby, also, wear of the brake shoes may bereadily compensated for by adjustment of the brake heads, and as aresult thereof the braking power may be conserved.

To this end the main feature of my invention embraces the combination ina brake mechanism for car trucks, of a brake shoe movably connected withthe truck, and mat ing cam devices for applying the brake shoes to thewheels when power is applied, one of which mating cam devices isconnected with the mechanism which transmits the braking power and theother of which mating cam devices co-acts with the car-bolster throughthe mediation of a yielding means, whereby the load on the cardetermines and controls the braking pressure applied by the brake-shoesto the wheels.

There are other, minor, features of inven tion involving particularcombinations and elemental features of construction, ancillary to themain features of invention, all of which will hereinafter more fullyappear.

1n the drawings chosen for the purpose of illustrating my invention, thescope whereof is pointed out in the claims, Figure 1 is a plan view of acar truck showing the brake mechanism embodying my invention,illustrating the preferred form thereof. Fig. 2 is a vertical section ofthe truck and brake mechanism embodying my invention, taken in the planeof the line 22 Fig. 1. Fig. 3 is a plan view of a car truck and brakemechanism embodying my invention in a modified form, wherein brakelevers and brake beams of substantially the construction now in use areutilized. Fig. 4 is a vertical sect-ion of a car truck and brakemechanism embodying my invention in the modified form, taken in theplane of the line 4-4 Fig. 3. Fig. 5 is an end view of the car truck andbrake mechanism shown in Fig. 3, the near axle and wheels being removedand the near brake heads broken away. Fig. 6 is a vertical sectionalview of a car truck and brake mechanism embodying a further modificationin the arrangement of the brake mechanism. Fig. 7 is a verticalsectional view of a car truck and modification of brake mechanismembodying my invention, showing an arrangement thereof especiallyadapted for use where it is desired to apply the brake shoes between andbelow the wheel centers. Fig. 8 is a detail view of a portion of theside frame of a car truck and a brake shoe support slidably mountedthereon. Fig. 9 is a top or plan view of the portion of car truck andbrake shoe slide shown in Fig. 8, the brake shoe being omitted.

Like symbols refer to like parts wherever they occur.

I will now proceed to describe my invention more fully so that othersskilled in the art to which it appertains may apply the same.

In the drawings, A, A indicate the side frames of a car truck, 13,13 thewheels of the truck, C the bolster, D the bolster springs, E the springplank, and F the spring plank saddle, all of which may be of theconstruction shown, or any approved construction.

1, 1 indicate the brake shoes and brake heads, which are movablyconnected with the side frame in any suitable manner, so as to beindependent of each other.

In the preferred form of construction the connections between each brakeshoe and the car truck is in the form of an arm or lever 2 pivoted onthe side frame as at 2 and the brake shoe 1 is located above the centerof the wheel so that when the braking power is applied the tendency isto press the wheel downward.

Upon the upper surface of the brake shoe arm or lever 2 is one member 8of mating cam devices 8, 4, through which the braking power of the airbrake mechanism is applied to the brake shoe. These mating cam clevices3, 4 are preferably of tubular form for the passage of a bolt or red andare provided with helical bearing faces whereby the relative rotation ofsuch mating cam devices causes a relative linear movement of themembers.

The rotary member 4 of the mating cam devices, in the preferredconstruction, Figs. 1 and 2 of the drawings, is located over and restsupon the non-rotary or fixed cam member 3 on the brake shoe arm 2, andthis rotary member 4 is provided with crank arms whereby it may berotated and through which it may be connected with and rotate likemembers which coact with other brake shoes.

InFigs. 1 and 2 of the drawings the pre ferred form of applying thebraking power to the cam devices is shown in full lines, wherein Pindicates the pull rod which is connected with the crank arm 5 of thefirst rotary cam member 4 and this crank arm is in turn connected by arod or link 79- with the neXt crank arm 5, which in turn is connectedthrough crank arm 6 and rod or link 72' with the third crank arm 5 andthis latter is in turn connected with the last cam device 4 by means ofcrank arms 6 and connecting rod 79 If a central position of the pull rodP is required, or desired, the connecting rod 2) may be omitted andconnec tions made as indicated by dotted lines Fig. 1. v

The cooperative relations of the members 3 and 4 of the mating camdevices is maintained by the bolt 7 which passes through them. This bolt7 has a point of attachment or support either on the side frame of thecar truck or some element of the construction carried thereby that willcause the bol ster springs and load on the bolster to resist themovement of said bolt 7.

In the preferred form of the construction illustrated in Figs. 1 and 2of the drawings the bolt 7 passes through an eye f on the horn of saddleF which carries the sp "ing plan E and bolster springs D. The bolt 7 isencircled by a spiral release spring 8 one end of which rests on thehorn of the saddle F and the other bears against the under side of thebrake shoe arm or brake shoe lever 2. The bolt 7 is threaded at itsupper end and provided with a nut n for maintaining and adjusting theconnection between the saddle, bolt, release spring, lever or brake shoearm, and mating cam devices. The function of the spring 8 is to hold thebrake shoe away from the wheel when the braking power is off, and thedistance of the brake shoe from the wheel will depend on the operativelength of the bolt 7 so that by means of the nut a the brake shoe can beadjusted to take up wear and determine the distance the brake shoe mustmove when the brakes are applied. The saddle F is riveted, or otherwiseconnected, to and supported from the spring-plank E, as indicated at 9.

In Figs. 3, 4 and 5 of the drawings, a

modification of the arrangement of the mating cam devices is shown, aswell as a modification in the means for applying the brak ing power tothe mating cam devices. In this modification, the saddle on which thespring plank rests is omitted; the fixed or non-rotary cam member 8ofthe mating cam devices is formed integral with or connected directlyto the side frame A of the car truck. the crank arm 5 of the rotarymember 4? of the mating cam devices is connected to one of the beams 10,10, which beams are provided with the usual brake levers 11, 11 andconnecting rod 12, and the lever 11 is connected with the pull rod P ofthe air brake mechanism. In this arrangement the release spring 8 whichencircles the bolt 7 is interposed between the fixed member 8 of the camdevices and the brake shoe arm or lever 2.

In the modification shown in Fig. 6 of the drawings, the saddle F isattached to the spring plank E, the fixed non-rotary cam member 3* ofthe mating cam devices is formed on the horn of the saddle, and therelease spring 8* is interposed between the horn of the saddle F and thebrake shoe arm or brake shoe lever 2. In this construc tion the rotarymember 4 of the mating cam devices is located below the member 3 andbelow the horn of saddle F and is confined by the nut n.

In the modification shown in Fig. 7, which is adapted for thoseconstructions where the brake shoe is to be applied between the wheelsand below the centers thereof, the brake shoes are movably connectedwith the spring plank by short links 13 and suspended from bolt 7 whichpasses through the annular mating cam devices 3 and 4. The fixed ornon-rotary cam member 3 is formed on or attached to the side frame A ofthe truck, while the rotary cam member 4 is supported by and confined tothe cam device member 3 by a suitable nut. The crank arms 5 and 6 of therotary cam members 4 are operatively connected with each other and withthe pull rod as illustrated in Fig. 1 of the drawings.

In Figs. 8 and 9 of the drawing there is shown a modified form of themovable connection between the brax shoe and the side frame of the cartruck which may be adopted instead of using the pivoted arm 2, Figs. 2and i, if desired. In this construction the brake head and brake shoeare mounted directly on a slide l i movable in ways 15 on the side frameA of the car truck. With this slide 14 the bolt 7 which passes throughthe mating cam devices 3 and a is connected, and a spiral release spring8 is interposed between the head of the belt which is connected with theslide and th fixed or non-rotary cam member 3 of the mating cam devices.The fixed 0r non-rotary cam members 3 of the mating cam devices issecured to the side-frame A of the car truck, and the rotary member 46of the cam devices is located below the member 3 and confined by a nutin the usual manner.

The brake mechanism being constructed and combined as hereinbeforepointed out will operate as follows: In the construct-ion illustrated inFigs. 1 and 2 the braking power applied to the pull rod P will betransmitted through the intermediate devices to the several rotarymembers 4 of the mating cam devices, these cam members t being thusrotated on their respective bolts 7 and on their corresponding matingcam members 8. The initial rotation of the cams 4 causes the brake-shoelevers 2 to be de pressed, thus compressing the release springs 8 andbringing the brake-shoes 1 into contact with their respective wheels B.When the brake-shoes have thus come into contact with the wheels of thetruck, the further rotation of the cams 4 imparts an upward, liftingforce to the bolts 7 and a downward, braking pressure of the brake-shoesupon the wheels. As the bolts 7 are connected to the spring-plank saddleF in such manner as to be capable of exerting upward force upon thesaddle, the upwardly directed force applied to the bolts 7 by the rotarycams e is transmitted to the bolster C and its superposed car bodythrough the bolster springs D thus lifting or tending to lift, accordingas the load is light or heavy, the car body and its load, and therebypermitting the power applied by the rotary cams 4c in excess of thatnecessary to overcome the weight of the car to be expended in the workof lifting the car. Where my brake mechanism is applied to a form oftruck in which the spring-plank is relatively movable vertically withrespect to the side-frames any upward pull of the bolts 7 upon thespring-plank saddle F in excess of that necessary to counterbalance theweight of the parts supported on the springplank will cause the latterto move upwardly with respect to the side frames. Where my brakemechanism is applied to a type of truck in which the spring-plank andsideframes are rigidly connected any force ap plied to the bolts 7sufiicient to overcome the load carried on the bolster and side frameswill lift the latter and thus cause a corresponding elevation of the carbody and its load. By this means the braking force of the brakeshoes lon the wheels 3 is rendered proportional to the load carried by thetruck bolster C.

The form of construction illustrated in Figs. 3. 4 and 5 of the drawingsoperates in substantially the same manner that just described, anytendency to an excessive pull upon the bolts 7 being relieved by thelifting of the side-frames and a corresponding elevation of the bolsterand its superposed. load. The construction shown in Fig. 6 also operatesin substantially the same manner as the mechanism illustrated in Figs. 1and 2, the only substantial differences being that the rotary cams 4Poperate directly upon the spring-plank saddle F and cause a downward,instead of an upward, pull upon the bolts connected to the brake-shoelevers 2.

In the modified form of construction illustrated in Fig. 7 of thedrawings, the toggle action of the links 13, acting upon thespring-plank E, causes any excessive braking power applied by the rotarycams a to be expended in lifting the load imposed upon the bolster C.The construction illustrated in Figs. 8 and 9 operates in substantiallythe same manner as the brake mechanism shown in Figs. 3, t and 5, slides1a which bear the brake-shoes 1 being mounted upon the side-frames A ofthe truck and serving to perform the functions of the brake-shoe levers2.

Having thus described my invention, what I claim and desire to secure byLetters Patent, is:

1. In a brake mechanism for car trucks, the combination with a truckside frame and bolster, of a brake shoe movably connected with the sideframe of the car truck, mating cam devices for transmitting brakingpower to the brake shoe, and yielding means operatively interposedbetween the bolster and the cam devices for limiting the pressure of thecam devices on each other.

2. In a brake mechanism for car trucks, the combination with a car truckside frame, a bolster, and bolster springs, of a brake shoe movablyconnected with the side frame, mating cam devices for actuating thebrake shoe, and means interposed between one of the cam devices and thebolster, whereb the load on said bolster may be transmitted to said camdevice.

3. In a brake mechanism for car trucks, the combination with a car truckside frame, a bolster, and bolster springs, of a brake shoe movablyconnected with the side frame, mating cam devices for actuating thebrake shoe, and means interposed between one of the members of the camdevice and the bolster, whereby the load on said bolster may betransmitted to the cam devices.

4. In a brake mechanism for car trucks, the combination with a sideframe and bolster, of a brake shoe, a brake shoe lever pivoted on theside frame, mating cam devices for actuating the brake shoe lever, andmeans operatively interposed between the bolster and the mating camdevices, for

Copies of this patent may be obtained for five cents each, by addressingthe transmitting the load on the bolster to the cam devices.

5. In a brake mechanism for car trucks, the combination with a sideframe, a bolster and bolster springs, of a brake shoe lever pivoted onthe side frame, mating cam devices for actuating the brake shoe, one ofsaid cam devices being located on the brake shoe lever, and meansinterposed between one of the camdevices and the bolster whereby theload on said bolster may be transmitted to the cam devices.

6. In a brake mechanism for car trucks, the combination with a car truckside frame, a bolster, and bolster springs, of a brake shoe, a brakeshoe lever pivoted on the side frame, mating cam devices for actuatingthe brake shoe lever, a saddle interposed between the bolster springsand mating cam devices, and means for connecting the saddle with themating cam devices, whereby the load on the bolster may be transmittedto the cam device.

7 In a brake mechanism for car trucks, the combination with a car truckside frame, a bolster, and bolster springs, of a brake shoe movablyconnected with the side frame, mating cam devices for actuating thebrake shoe, means interposed between said cam devices and the bolsterwhereby the load on said bolster may be transmitted to said cam device,and a spring for moving the brake shoe from braking position whereby thebrake shoe is held out of engagement with the car wheel when released bythe cam devices.

8. In a brake mechanism for car trucks, the combination with a car truckside frame, of a brake shoe movably connected therewith, mating camdevices for actuating the brake shoe, a release spring for the brakeshoe, and a bolt for connecting the release spring and the mating camdevices with each other and with the movable brake shoe.

9. In a brake mechanism, the combination of a car truck side frame,spring plank, springs, independent brake shoe lever arms having avertical movement, and means independent of the movement of the car bodyfor inducing a downward movement of said lever arms when braking poweris applied and for inducing an upward pressure on said springs.

In testimony whereof I aflix my signature, in the presence of twosubscribing witnesses.

HARRY G. BUI-IOUP.

lVitnesses:

D. B. Mason, I-IARRY W. STANNARD.

Commissioner of Patents,

Washington, D. G.

